The present invention relates generally to data storage media and, more particularly, to a wiper spring assembly which biases a fabric liner against a floppy disc.
Widely used in the computer industry is a data storage medium including a "floppy disc" which is coated with magnetic particles and is positioned in a protective "jacket." The jacket includes a base, a cover and a fabric liner. The floppy disc, while in use, is constantly cleaned by the wiping action of the fabric liner.
The fabric liner has to be biased upwardly against the floppy disc by some means within the jacket. This means is presently a plastic "wiper spring," usually polyester, located between the jacket base and the fabric liner and attached to a flat area of the jacket base by adhesive. This conventional wiper spring is shown in FIGS. 1 and 2 herein.
The conventional wiper spring requires that a crease be formed therein to force the floating, free end of the wiper spring up against the fabric liner, which liner in turn presses against the floppy disc. This spring action not only causes the cleaning action but also creates a drag on the floppy disc measured as torque. It is important that this torque be as constant as possible to induce rotational stability in the floppy disc and reduce the chance of harmonic vibration being created on the floppy disc.
Use of the conventional wiper spring has its drawbacks, however, because a plastic spring does not exert the desired force at a constant compressed height over an extended period of time. In addition, a plastic spring is susceptible to gage variations, as well as other material variations during the plastic manufacturing process, which are substantial enough to cause a wide variation in the force exerted by the plastic wiper spring.
In light of the above, the prior art still does not teach a wiper spring which biases the fabric liner of a floppy disc to provide the most efficient operation of the floppy disc.